function gradientColor(startColor, endColor, step) {
  var startRGB = colorRgb(startColor);//转换为rgb数组模式
  var startR = startRGB[0];
  var startG = startRGB[1];
  var startB = startRGB[2];
  var endRGB = colorRgb(endColor);
  var endR = endRGB[0];
  var endG = endRGB[1];
  var endB = endRGB[2];
  var sR = (endR - startR) / step;//总差值
  var sG = (endG - startG) / step;
  var sB = (endB - startB) / step;
  var colorArr = [];
  for (var i = 0; i < step; i++) {
      //计算每一步的hex值
      var hex = colorHex('rgb(' + parseInt((sR * i + startR)) + ',' + parseInt((sG * i + startG)) + ',' + parseInt((sB * i + startB)) + ')');
      colorArr.push(hex);
  }
  return colorArr;
}
// 将hex表示方式转换为rgb表示方式(这里返回rgb数组模式)
// gradientColor.prototype.colorRgb = function (sColor) {
function colorRgb(sColor) {
  var reg = /^#([0-9a-fA-f]{3}|[0-9a-fA-f]{6})$/;
  var sColor = sColor.toLowerCase();
  if (sColor && reg.test(sColor)) {
      if (sColor.length === 4) {
          var sColorNew = "#";
          for (var i = 1; i < 4; i += 1) {
              sColorNew += sColor.slice(i, i + 1).concat(sColor.slice(i, i + 1));
          }
          sColor = sColorNew;
      }
      //处理六位的颜色值
      var sColorChange = [];
      for (var i = 1; i < 7; i += 2) {
          sColorChange.push(parseInt("0x" + sColor.slice(i, i + 2)));
      }
      return sColorChange;
  } else {
      return sColor;
  }
};
// 将rgb表示方式转换为hex表示方式
// gradientColor.prototype.colorHex = function (rgb) {
function colorHex(rgb) {
  var _this = rgb;
  var reg = /^#([0-9a-fA-f]{3}|[0-9a-fA-f]{6})$/;
  if (/^(rgb|RGB)/.test(_this)) {
      var aColor = _this.replace(/(?:(|)|rgb|RGB)*/g, "").split(",");
      var strHex = "#";
      for (var i = 0; i < aColor.length; i++) {
          var hex = Number(aColor[i]).toString(16);
          hex = hex < 10 ? 0 + '' + hex : hex;// 保证每个rgb的值为2位
          if (hex === "0") {
              hex += hex;
          }
          strHex += hex;
      }
      if (strHex.length !== 7) {
          strHex = _this;
      }
      return strHex;
  } else if (reg.test(_this)) {
      var aNum = _this.replace(/#/, "").split("");
      if (aNum.length === 6) {
          return _this;
      } else if (aNum.length === 3) {
          var numHex = "#";
          for (var i = 0; i < aNum.length; i += 1) {
              numHex += (aNum[i] + aNum[i]);
          }
          return numHex;
      }
  } else {
      return _this;
  }
}

export {
  gradientColor
}
